Hostname: page-component-586b7cd67f-t7czq Total loading time: 0 Render date: 2024-11-24T13:32:07.028Z Has data issue: false hasContentIssue false

Equivalence relations that act on bundles of hyperbolic spaces

Published online by Cambridge University Press:  03 April 2017

LEWIS BOWEN*
Affiliation:
Mathematics Department, 1 University Station C1200, University of Texas at Austin, TX 78712, USA email [email protected]

Abstract

Consider a measured equivalence relation acting on a bundle of hyperbolic metric spaces by isometries. We prove that every aperiodic hyperfinite subequivalence relation is contained in a unique maximal hyperfinite subequivalence relation. We classify elements of the full group according to their action on fields on boundary measures (extending earlier results of Kaimanovich [Boundary amenability of hyperbolic spaces. Discrete Geometric Analysis(Contemporary Mathematics, 347). American Mathematical Society, Providence, RI, 2004, pp. 83–111]), study the existence and residuality of different types of elements and obtain an analog of Tits’ alternative.

Type
Original Article
Copyright
© Cambridge University Press, 2017 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Adams, S.. Indecomposability of equivalence relations generated by word hyperbolic groups. Topology 33(4) (1994), 785798.Google Scholar
Adams, S.. Reduction of cocycles with hyperbolic targets. Ergod. Th. & Dynam. Sys. 16(6) (1996), 11111145.Google Scholar
Anderegg, M. and Henry, P. P. A.. Actions of amenable equivalence relations on CAT(0) fields. Ergod. Th. & Dynam. Sys. 34(1) (2014), 2154.Google Scholar
Boutonnet, R. and Carderi, A.. Maximal amenable von Neumann subalgebras arising from maximal amenable subgroups. Geom. Funct. Anal. 25(6) (2015), 16881705.Google Scholar
Bridson, M. R. and Haefliger, A.. Metric spaces of non-positive curvature. Grundlehren der Mathematischen Wissenschaften (Fundamental Principles of Mathematical Sciences, 319) . Springer, Berlin, 1999.Google Scholar
Cameron, J., Fang, J., Ravichandran, M. and White, S.. The radial masa in a free group factor is maximal injective. J. Lond. Math. Soc. (2) 82(3) (2010), 787809.Google Scholar
Connes, A., Feldman, J. and Weiss, B.. An amenable equivalence relation is generated by a single transformation. Ergod. Th. & Dynam. Sys. 1(4) (1982), 431450 1981.Google Scholar
Csoka, E. and Lippner, G.. Invariant random perfect matchings in Cayley graphs. Groups, Geometry, and Dynamics , to appear.Google Scholar
Conley, C. T., Marks, A. S. and Tucker-Drob, R. D.. Brooks’ theorem for measurable colorings. Forum Math. Sigma 4 (2016), e16, 23 pp.Google Scholar
Chifan, I. and Sinclair, T.. On the structural theory of II1 factors of negatively curved groups. Ann. Sci. Éc. Norm. Supér. (4) 46(1) (2013), 133 2013.Google Scholar
Feldman, J. and Moore, C. C.. Ergodic equivalence relations, cohomology, and von Neumann algebras. I. Trans. Amer. Math. Soc. 234(2) (1977), 289324.Google Scholar
Gaboriau, D.. Coût des relations d’équivalence et des groupes. Invent. Math. 139(1) (2000), 4198.Google Scholar
Gaboriau, D.. Examples of groups that are measure equivalent to the free group. Ergod. Th. & Dynam. Sys. 25(6) (2005), 18091827.Google Scholar
Gaboriau, D. and Lyons, R.. A measurable-group-theoretic solution to von Neumann’s problem. Invent. Math. 177(3) (2009), 533540.Google Scholar
Giordano, T. and Pestov, V.. Some extremely amenable groups related to operator algebras and ergodic theory. J. Inst. Math. Jussieu 6(2) (2007), 279315.Google Scholar
Hjorth, G.. Non-treeability for product group actions. Israel J. Math. 163 (2008), 383409.Google Scholar
Houdayer, C.. A class of II1 factors with an exotic abelian maximal amenable subalgebra. Trans. Amer. Math. Soc. 366(7) (2014), 36933707.Google Scholar
Jackson, S., Kechris, A. S. and Louveau, A.. Countable Borel equivalence relations. J. Math. Log. 2(1) (2002), 180.Google Scholar
Kaimanovich, V. A.. Boundary amenability of hyperbolic spaces. Discrete Geometric Analysis (Contemporary Mathematics, 347) . American Mathematical Society, Providence, RI, 2004, pp. 83111.Google Scholar
Kechris, A. S.. Global Aspects of Ergodic Group Actions (Mathematical Surveys and Monographs, 160) . American Mathematical Society, Providence, RI, 2010.Google Scholar
Kapovich, I. and Short, H.. Greenberg’s theorem for quasiconvex subgroups of word hyperbolic groups. Canad. J. Math. 48(6) (1996), 12241244.Google Scholar
Kechris, A. S., Solecki, S. and Todorcevic, S.. Borel chromatic numbers. Adv. Math. 141(1) (1999), 144.Google Scholar
Lyons, R. and Nazarov, F.. Perfect matchings as IID factors on non-amenable groups. European J. Combin. 32(7) (2011), 11151125.Google Scholar
Ol’shanskiĭ, A. Y.. Geometry of Defining Relations in Groups (Mathematics and its Applications Soviet Series, 70) . Kluwer Academic Publishers Group, Dordrecht, 1991. Translated from the 1989 Russian original by Yu. A. Bakhturin.Google Scholar
Ornstein, D. S. and Weiss, B.. Ergodic theory of amenable group actions. I. The Rohlin lemma. Bull. Amer. Math. Soc. (N.S.) 2(1) (1980), 161164.Google Scholar
Ozawa, N.. Solid von Neumann algebras. Acta Math. 192(1) (2004), 111117.Google Scholar
Pemantle, R. and Peres, Y.. Nonamenable products are not treeable. Israel J. Math. 118 (2000), 147155.Google Scholar
Peterson, J. and Thom, A.. Group cocycles and the ring of affiliated operators. Invent. Math. 185(3) (2011), 561592.Google Scholar
Shen, J.. Maximal injective subalgebras of tensor products of free group factors. J. Funct. Anal. 240(2) (2006), 334348.Google Scholar
Väisälä, J.. Gromov hyperbolic spaces. Expo. Math. 23(3) (2005), 187231.Google Scholar
Zimmer, R. J.. Ergodic Theory and Semisimple Groups (Monographs in Mathematics, 81) . Birkhäuser, Basel, 1984.Google Scholar